[web] Serve static assets

web/Cargo.toml

@@ -21,4 +21,12 @@ lazy_static = { version = "1.4.0", optional = true }
 # that supports OGP, the card will include a visual of their pronouns.
 ogp_images = ["rusttype", "image", "lazy_static"]
 
-default = ["ogp_images"]
+# Several assets are unchanging static assets, which by default can be served directly
+# from the binary.  If so, these assets will be embeded into the binary and copied into
+# memory when the binary runs.  To improve performance, you may elect to serve these
+# binaries using a webserver and reverse proxy.  If you choose to do so, you may
+# optionally disable this feature.  Doing so will remove the --dump-static-assets feature
+# flag, and will remove the ability to serve any static assets.
+embed_static_assets = []
+
+default = ["ogp_images", "embed_static_assets"]

web/src/main.rs

@@ -1,5 +1,6 @@
 pub mod ogp_images;
 pub mod contrast;
+pub mod statics;
 
 use std::collections::HashMap;
 use std::fmt::{self, Display};
@@ -148,6 +149,9 @@ async fn main() -> std::io::Result<()> {
             .wrap(middleware::NormalizePath::new(TrailingSlash::Trim))
             .service(create_link);
 
+		let app = statics::STATIC_ASSETS.iter()
+			.fold(app, |app, asset| app.service(asset.generate_resource()));
+
         #[cfg(feature = "ogp_images")]
         let app = app
             .service(resource("/thumb.png")               .to(handle_thumbnail_request))

web/src/ogp_images.rs

@@ -1,6 +1,7 @@
 #![cfg(feature = "ogp_images")]
 
 use crate::contrast::generate_color_pair_rgba;
+use crate::statics;
 
 use image::{DynamicImage, ImageBuffer, Pixel, Rgb, Rgba};
 use lazy_static::lazy_static;
@@ -9,9 +10,8 @@ use rusttype::{Font, Scale, point};
 
 const SCALE: u32 = 400;
 const FONT_SCALE: f32 = 250.0;
-const FONT_DATA: &[u8] = include_bytes!("../assets/LeagueGothic.otf");
 lazy_static! {
-	static ref FONT: Font<'static> = Font::try_from_bytes(FONT_DATA)
+	static ref FONT: Font<'static> = Font::try_from_bytes(statics::FONT.bytes)
 		.expect("Invalid font data in build.  This build and binary is invalid, and cannot be used.");
 }
 

web/src/statics.rs

@@ -0,0 +1,70 @@
+use actix_web::http::StatusCode;
+use actix_web::HttpResponse;
+use actix_web::HttpRequest;
+use actix_web::web::resource;
+use actix_web::Resource;
+
+/// Represents a single static asset
+///
+/// Each asset is embeded into the binary, and can be served under the
+/// `/static/{filename}` route.  All static assets should be embeded in this way, and can
+/// be referenced from this module.
+pub struct StaticAsset {
+
+	/// The filename of this asset relative to `:/web/assets/` and the `/static/` route
+	pub filename: &'static str,
+
+	/// The content of the file
+	pub bytes: &'static [u8],
+
+}
+
+impl StaticAsset {
+	/// Generate a actix resource for serving this asset
+	///
+	/// The resource will handle requests at `/static/{filename}`.  Caching headers are
+	/// applied to allow the content to be considered fresh up to one day, and are
+	/// validated against the crate version after that.
+	pub fn generate_resource(&self) -> Resource {
+		let bytes = self.bytes;
+		resource(format!("/static/{}", self.filename))
+			.to(move|req: HttpRequest| async move {
+				let mut response = HttpResponse::Ok();
+				response
+					.header("Etag", env!("CARGO_PKG_VERSION"))
+					.header("Cache-Control", "max-age=86400");
+
+				let req_etag = req.headers().get("If-None-Match");
+				match req_etag {
+					Some(etag) if etag == env!("CARGO_PKG_VERSION") => {
+						response.status(StatusCode::from_u16(304).unwrap()).finish()
+					}
+					_ => {
+						response.body(bytes)
+					}
+				}
+			})
+	}
+}
+
+
+/// Generate a [`StaticAsset`] at compiletime from a filename.
+#[cfg(any(feature = "embed_static_assets", feature = "ogp_images"))]
+macro_rules! static_asset {
+	( $filename: expr ) => {
+		StaticAsset {
+			filename: $filename,
+			bytes: include_bytes!(concat!("../assets/", $filename)),
+		}
+	}
+}
+
+/// The decorative font to be used for pronouns displayed at a very large size
+#[cfg(any(feature = "embed_static_assets", feature = "ogp_images"))]
+pub const FONT: StaticAsset = static_asset!("font.otf");
+
+/// A list of static assets which should be served by the server
+pub const STATIC_ASSETS: &[StaticAsset] = &[
+	#[cfg(any(feature = "embed_static_assets"))]
+	FONT,
+];